1. Field of the Invention
The present invention relates to a machine tool having a carriage disposed on a fixed bed on a front side closer to an operator while a headstock is provided on a rear side farther from the operator.
2. Discussion of the Related Art
There has conventionally been mass production type machine tools such as a Numerically Controlled lathe (also called a NC lathe) where carriages, each with a tool post mounted thereon, are provided on the left and right sides of a front side of the fixed bed that is closer to the operator. The tool posts and the carriages are movable in the X-axis and Z-axis directions, respectively. A headstock is fixedly disposed on the rear side (side farther from the operator) between the two tool posts.
In these types of machine tools, a workpiece is loaded onto the spindle of the headstock. Then, while the workpiece is being rotated, the left and right carriages and tool posts are moved relative to each other, so as to subject the workpiece to a specified cutting process.
In a conventional machine tool, because its structure of the headstock is fixedly disposed rearwardly of the left and right carriages, loading and unloading the workpiece on the spindle with another workpiece must be done at a significant depth of the fixed bed, thereby causing some difficulty for the operator and a lower operational efficiency.
Also, in some conventional machine tools, chips resulting from the machining processes are discharged toward the operator. In such machine tools, these chips tend to be an obstacle to loading and unloading the workpiece and this also reduces operational efficiency and convenience.